The present disclosure relates to a data communication method and an information processing device capable of establishing a plurality of TCP (Transmission Control Protocol) connections between a server device and a client device and communicating each piece of data, which is divided for each prescribed unit, through the plurality of TCP connections.
In the related art, there is a widely used method of communicating web pages and contents from the service on the Internet through HTTP (HyperText Transfer Protocol). For example, it is possible to perform download (GET) or upload (PUT) of data through HTTP.
Generally, HTTP is performed on a single TCP. The TCP is a transport capable of asynchronous bidirectional communication. In HTTP, an information processing device as a client and an information processing device as a server interchange the requests for the download (GET) or the upload (PUT) of the data or the replies to the requests through a single TCP connection. Specifically, the client transmits the upload request (PUT request), and then transmits the data to be uploaded subsequently to the PUT request. On the other hand, when the client transmits the download request (GET request), the server transmits the reply to the GET request, and transmits the data which is downloaded subsequently to the reply.
Here, the throughput per one TCP under the environment, which is a sufficiently large bandwidth and in which delay is large, depends on the method of the flow control of the TCP. Here, the maximum throughput is obtained by the receive buffer size per socket/RTT (Round Trip Time, the time necessary for the round trip of a packet). When the maximum throughput of the TCP is limited by the above factors, under the environment which is a sufficiently large bandwidth and in which delay is large, there is a concern that the original ability of the link is not sufficiently exhibited.
For this reason, there has been proposed SPDY which is a standard as a communication protocol of the Internet contents in replacement of HTTP (for example, refer to the online document “SPDY” on the Internet <URL: http://www.chromium.org/spdy> (Searched on Oct. 18, 2010)). In SPDY, there is an improvement in that it is possible to efficiently transmit various contents of the Internet even one TCP by changing the layer of HTTP. SPDY provides a clue to solve problems caused by HTTP (for example, it is necessary to complete the communication of the data in sequence of the requests, and so on) and a clue to enable a browser to perform efficient pre-reading.
Further, there has been proposed a method of transmitting data in parallel through HTTP by using the plurality of TCP connections (for example, refer to Japanese Unexamined Patent Application Publication No. 2005-57482).